. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 100 C. LADD PROSSER bition is altered little if any but the duration of threshold inhibition is very greatly lengthened. In one experiment, for example, an inhibitory stimulus which before eserinization caused inhibition lasting approxi- mately 30 seconds, after eserinization resulted in inhibition which lasted 50 minutes. Recovery from the effect of eserine is very slow; in these experiments it was appreciable after one-half hour but was not usually complete after several hours. These results indicate that the effect of B.
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 100 C. LADD PROSSER bition is altered little if any but the duration of threshold inhibition is very greatly lengthened. In one experiment, for example, an inhibitory stimulus which before eserinization caused inhibition lasting approxi- mately 30 seconds, after eserinization resulted in inhibition which lasted 50 minutes. Recovery from the effect of eserine is very slow; in these experiments it was appreciable after one-half hour but was not usually complete after several hours. These results indicate that the effect of B. FIG. 5. Effect of eserine sulphate upon inhibition of the heart. A and B chamber preparation. A, inhibition by threshold concentration of acetylcholine 10~10. B, inhibition due to same concentration of acetylcholine combined with eserine (10~4) after eserinization for approximately 15 minutes. Eserine alone had no perceptible effect upon beat. C and D in situ preparation. C, inhibition of heart bathed with sea water by visceral ganglion stimulation at indicated positions of inductorium secondary. D, inhibition at same intensities of ganglion stimulation after 20 minutes of eserinization. Time interval in A and B, 3 seconds; in C and D, 10 seconds. eserine is not to sensitize the heart but to prevent destruction of the inhibitory mediator. If acetylcholine is the mediator involved its action should be greatly prolonged because its hydrolysis by choline esterase is retarded. This is found to be true. It is of interest that Bacq (1935) found a moderate amount of choline esterase in the blood of the pelecypod, Pectunculus, and in other molluscan tissues. He found several molluscan body muscles to respond. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Marine Biological Laboratory (Woods Hole, Mass. ); Marine Bi
Size: 1862px × 1342px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
